EP 0537960 A1 19930421 - Adjustable bandwidth in a radio telephone.
Title (en)
Adjustable bandwidth in a radio telephone.
Title (de)
Verstellbare Bandbreite eines Funktelefons.
Title (fr)
Radiotéléphone à largeur de bande réglable.
Publication
Application
Priority
US 77934791 A 19911017
Abstract (en)
The frequency of a first local oscillator signal (1.LO) is offset in reference to the center frequency of a first bandpass filter (4), and the frequency of a second local oscillator signal (2.LO) is offset in reference to the center frequency of a second bandpass filter (7). The frequency offsets are selected so that only a portion (x, y) of the filter (4, 7) bandwidths (bw, BW) will add to an "imaginary" effective narrow bandwidth (NBW). The amounts of frequency offset are continuously adjustable by programmable controlling means. <IMAGE>
IPC 1-7
IPC 8 full level
H04B 1/10 (2006.01); H04B 1/26 (2006.01); H04W 88/02 (2009.01)
CPC (source: EP US)
H04B 1/1027 (2013.01 - EP US); H04B 2001/1054 (2013.01 - EP US)
Citation (search report)
- [X] US 4267605 A 19810512 - MATSUZAWA MITSUO, et al
- [A] US 3953802 A 19760427 - MORRIS GEORGE F, et al
Designated contracting state (EPC)
DE FR GB SE
DOCDB simple family (publication)
EP 0537960 A1 19930421; EP 0537960 B1 19980304; DE 69224581 D1 19980409; DE 69224581 T2 19980730; JP 3174412 B2 20010611; JP H05227051 A 19930903; US 5303404 A 19940412
DOCDB simple family (application)
EP 92309255 A 19921012; DE 69224581 T 19921012; JP 27843292 A 19921016; US 77934791 A 19911017